sfplay~ report duration?

I’m having trouble figuring out how to get sfplay to report the duration of a loaded soundfile similarly to the way the "getduration" message works in jit.qt.movie. I’ve looked at the help file and the reference doc to no avail. Maybe sfplay can’t do this? if it can’t is there some other object I can use to play back audio files that I can program to report duration when a file is loaded?